I’m facing a storage mismatch issue on Fedora (Btrfs), and I’ve already done extensive debugging but can’t locate ~130GB of used space.
System:
- Fedora 43 (GNOME)
- Filesystem: Btrfs
- Single disk (~278GB)
Problem:
- "df -h" shows ~240GB used
- "du -h /" shows only ~100GB
- Missing ~130–140GB
What I’ve checked:
- "/home" = ~82GB
- "/usr" + "/var" ≈ ~20GB
- Flatpak apps + runtimes small
- Docker almost empty
- No Timeshift/Btrfs snapshots
- "btrfs subvolume list" → only root + home
- No deleted files held open ("lsof | grep deleted")
- No hidden "/home" under root subvolume
- Btrfs balance ("dusage=0,1,5") did nothing
- Btrfs scrub running
- "/var/lib" not large
- ".var", ".local", ".cache" inspected
Btrfs stats:
- Data used: ~229GB
- But visible files ~100GB
Confusion:
Where is the remaining ~130GB?
It doesn’t appear in "du", not in subvolumes, not in mounts I checked.
What I suspect:
- hidden mount/bind mount?
- Btrfs accounting issue?
- something "du" is not traversing?
Outputs (attached):
- "df -h"
- "btrfs filesystem usage /"
- "findmnt -t btrfs"
- "du -h --max-depth=1 /"
- "du -h --max-depth=1 /home/Manu"
Any help would be appreciated. I want to understand the root cause before considering reinstall.